As title says, copper bars are not craftable and recipes will not show up in JEI
Tested in a fresh 1.18.2 world with forge 40.1.25, additional bars 3.0.1 Beta+1.18.2
Also during testing i found that even gold bars were not craftable either, even though the modpack i originally found this issue in has gold bars craftable, and nothing changed for them

Okay cool i'll pass that on.

This is intentional because copper bars don't have most of the functionality implemented, such as waxing, stripping and lightning striking.

I'm waiting for MinecraftForge/MinecraftForge#8363 to get merged to implement full functionality and crafting